What a moment for President Obama to deliver his valedictory address to the UN on Tuesday -- defending the liberal international order at a time when it’s under severe stress around the world.

Obama’s speech was preceded by some sickening reminders of how global security is fraying: The day before, a Syrian, or perhaps Russian, airstrike had ravaged a UN aid convoy trying to relieve Aleppo; over the weekend, a lone-wolf terrorist had tried to slaughter innocents in the New York area; three days before, errant American bombs had incinerated a camp of Syrian soldiers and, in the process, torched a fragile cease-fire.

Amid this disordered world, Obama displayed his sterling assets: his idealism, moral clarity and calm intellect. But those good qualities seemed unequal this past week to containing the bad forces that are loose in the world. As this gifted but sometimes vexed leader prepares to leave office, the world seems more disordered than when he arrived. He has been a creature of light at a time when the world was darkening.

Obama’s address was personal and polyphonous: One part was a campaign speech, touting “the progress that we’ve made these last eight years” and criticizing “crude populism,” an obvious reference to Donald Trump. Another part could have been delivered in a Bible-study class, arguing against a world of cynical self-interest and proposing instead that his audience of hardened global political leaders become, echoing Martin Luther King, “co-workers with God.”

Through the speech, you could hear early soundings of the memoir he must already be starting to compose in his head. He spoke of his multiracial background and his rise to power as evidence that “our identities don’t have to be defined by putting someone else down.” He might have been arguing with the gloomy philosopher Thomas Hobbes when he insisted that each individual or nation “can choose to reject those who appeal to our worst impulses and embrace those who appeal to our best.”

Discussing the Middle East sinkhole he tried so hard to escape, but which ended up swallowing much of his foreign-policy attention, he was remarkably frank: “So much of the collapse in order has been fueled (by) leaders ... resorting to persecuting political opposition, or demonizing other religious sects, (or) by narrowing the public space to the mosque.” Obama said out loud many of the feelings Jeffrey Goldberg attributed to him in his famous Atlantic article.

The centerpiece of the speech was Obama’s discussion of the liberal international order. This has become a kind of code-phrase for the American internationalism and global leadership that shaped the decades after 1945. Obama described “deep fault lines” that have emerged in this structure and societies that are now “filled with uncertainty, and unease, and strife.”

Rather than simply defending the old regime, Obama rightly argued for a “course correction” in globalization, so that it’s perceived as fairer and more inclusive. Escape is not an option, as Trump and others sometimes suggest. “We cannot unwind integration any more than we can stuff technology back into a box,” Obama argued.

The answer is better jobs, higher wages, and freer markets around the world. Listening to this change agenda, I found myself wishing that Obama had found the vision and political leverage to get it started four years ago, when there was more time.

The weakening of the old American-led order has been accompanied by the rise of a bullying (but weak) Russia and a strong China. Obama took on both challenges directly, arguing that recent power grabs in Ukraine and the South China Sea will ultimately backfire. Dreams of restored, neo-imperial Russia may be popular there, but they will ultimately “diminish its stature and make its borders less secure.” And China will lose security, rather than gain it, through “militarization of a few rocks and reefs.”

Good for Obama, too, in pushing back against Russian propaganda about the evils of US pro-democracy campaigns. “The people of Ukraine did not take to the streets because of some plot imposed from abroad. They took to the streets because their leadership was for sale and they had no recourse.” This was blunt, undiplomatic language -- and much needed.

Obama didn’t talk much about the hard power that would be necessary to roll back recent gains for the autocrats and restore a liberal global order. Such a policy, let’s call it “Obama Heavy,” would be the challenge for a President Hillary Clinton, if she can get past the finish line first in November.

Obama will leave behind the right ideas for restoration of an American-led order but sadly, also, the inescapable fact of its decline during his presidency.    

By David Ignatius 

David Ignatius’ email address is davidignatius@washpost.com. –Ed. 

(Washington Post Writers Group)